The efficacy and safety of articaine versus lignocaine in dental treatments: a meta-analysis

Katyal V

CRD summary

This review concluded that articaine was more effective than lignocaine in providing anaesthetic success in the first molar region for routine dental procedures and had similar adverse effect profiles. These conclusions should be interpreted with some caution due to the methodological limitations of the included studies and the possibility of language bias.

Authors' objectives

To compare the efficacy and safety of articaine with lignocaine in maxillary and mandibular infiltrations and block anaesthesia in patients presenting for routine dental treatments.

Searching

MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE and ProQuest Health and Medical Complete were searched from 1950 to October 2009; search strategies were reported in an appendix. Ongoing and unpublished studies were identified through searches of the metaRegister of Controlled Trials and by contacting the Australian manufacturer of the intervention. References of relevant reviews were screened. Language restrictions were not clearly reported; two studies were excluded as they were in German.

Study selection

Randomised controlled trials (RCTs) that compared 4% articaine with 2% lignocaine for maxillary and mandibular infiltrations and block anaesthesia in patients who required non-complex routine dental treatments were eligible for inclusion. Studies were required to report anaesthetic success, onset of action, post-injection adverse events or post-injection pain. Studies of computerised delivery routes were excluded. Studies that assessed pain had to report this using the Heft-Parker Visual Analogue Scale.

The anaesthetic dose for both articaine and lignocaine ranged from 0.9mL to 3.6mL. Injections were administered by infiltration, inferior alveolar nerve block and Gow-Gates block. Teeth anaesthetised were mandibular posteriors or first molars, maxillary posteriors, lateral incisor or first molars, or all teeth. Mean age, where stated, ranged from 23 to 36 years.

Two reviewers independently assessed studies for inclusion.

Assessment of study quality

Study quality was assessed based on criteria of random sequence generation, allocation concealment, blinding of examiners, handling of losses and analyses of losses. Each item was rated as adequate, inadequate or unclear. Explanations of ratings were recorded.

Validity assessment was performed by one reviewer. The authors stated that checking was performed several times; it was unclear whether the assessment for every study was checked.

Data extraction

Data were extracted as means and standard deviations to calculate mean differences (MDs) for continuous outcomes and as relative risks (RR) together with 95% confidence intervals (CIs) for dichotomous outcomes. Authors were contacted for additional information, where required.

Data extraction was performed by one reviewer. The authors stated that checking was performed several times; it was unclear whether the extraction for every study was checked.

Methods of synthesis

Summary mean differences and risk ratios together with 95% CIs were calculated using random-effects models. Heterogeneity was assessed visually using forest plots and statistically using I2. Planned subgroup analyses were based on age, gender, arch location, type of injection and dose of anaesthetic. Sensitivity analysis was conducted to assess the effects of low-quality RCTs.

Results of the review

Nine RCTs (n=1,725 participants, range 18 to 1,325) were included. Six trials were judged to have appropriate sequence generation. Four trials had adequately concealed treatment allocation. Seven trials were appropriately blinded. All trials either handled or analysed losses appropriately. Overall, five studies were judged to have rated poorly on the validity assessment.

Articaine was significantly more likely to achieve an anaesthetic success in the first molar area compared to lignocaine (RR 1.31, 95% CI 1.12 to 1.54; seven RCTs). Articaine was associated with significantly more pain than lignocaine post-infection on day zero (WMD 6.49, 95% CI 0.02 to 12.96; three RCTs), day one (WMD 5.35, 95% CI 0.83 to 9.88; three RCTs), day two (WMD 3.81, 95% CI 0.32 to 7.31; three RCTs) and day three (WMD 1.10, 95% CI 0.18 to 2.02; three RCTs). There was no difference between articaine and lignocaine in terms of onset of action in minutes (two RCTs), pain during solution deposition (three RCTs) and adverse events (four RCTs).

There was no evidence of heterogeneity for any analyses.

Authors' conclusions

Articaine was more effective than lignocaine in providing anaesthetic success in the first molar region for routine dental procedures. Both drugs appeared to have similar adverse effect profiles. The clinical impact of articaine's higher post-injection pain scores compared to lignocaine was negligible.

CRD commentary

The review addressed a focused question supported by clearly defined inclusion criteria. An extensive literature search was conducted and included attempts to locate unpublished data. Exclusion of two German-language papers raised the possibility of language bias, especially given the small number of included studies. Appropriate steps were taken to minimise bias and errors when selecting studies; it appeared that such steps were also taken when extracting data and assessing study quality, but the exact processes were not clearly reported. Study quality was assessed using relevant criteria and the results were reported in full. Appropriate methods were used to pool data and results were clearly presented with the aid of forest plots.

The authors' conclusions are supported by the data, but should be interpreted with some caution due to the methodological limitations of the included studies and the possibility of language bias.

Implications of the review for practice and research

Practice: The authors stated that articaine was a superior anaesthetic to lignocaine for use in routine dental procedures. Use in children under four years of age was not recommended as no data existed to support such usage.

Research: The authors stated that a uniform pain scoring should be developed to study the efficacy and safety of articaine in dental procedures for children. Research was needed to determine whether articaine had faster onset of anaesthesia than lignocaine as seen by doctors in the clinical setting. The quality of future trials, particularly in terms of allocation concealment and handling and analysis of losses, should be improved.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.